Le lundi 21 novembre 2011 à 21:18 -0600, Christoph Lameter a écrit : > Hmmm... That means that c->page points to page not frozen. Per cpu > partial pages are frozen until they are reused or until the partial list > is flushed. > > Does this ever happen on x86 or only on other platforms? In put_cpu_partial() the > this_cpu_cmpxchg really needs really to be irq safe. this_cpu_cmpxchg is > only preempt safe. > > Index: linux-2.6/mm/slub.c > =================================================================== > --- linux-2.6.orig/mm/slub.c 2011-11-21 21:15:41.575673204 -0600 > +++ linux-2.6/mm/slub.c 2011-11-21 21:16:33.442336849 -0600 > @@ -1969,7 +1969,7 @@ > page->pobjects = pobjects; > page->next = oldpage; > > - } while (this_cpu_cmpxchg(s->cpu_slab->partial, oldpage, page) != oldpage); > + } while (irqsafe_cpu_cmpxchg(s->cpu_slab->partial, oldpage, page) != oldpage); > stat(s, CPU_PARTIAL_FREE); > return pobjects; > } > For x86, I wonder if our !X86_FEATURE_CX16 support is correct on SMP machines. this_cpu_cmpxchg16b_emu() claims to be IRQ safe, but may be buggy... Could we have somewhere a NMI handler calling kmalloc() ? Please Markus send us : cat /proc/cpuinfo -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>